U.S. patent application number 12/488587 was filed with the patent office on 2009-12-24 for method for manufacturing dispersion and liquid mixing device.
This patent application is currently assigned to CANON KABUSHIKI KAISHA. Invention is credited to Yukio Hanyu, Tetsuo Hino, Takayuki Teshima.
Application Number | 20090318586 12/488587 |
Document ID | / |
Family ID | 41431886 |
Filed Date | 2009-12-24 |
United States Patent
Application |
20090318586 |
Kind Code |
A1 |
Teshima; Takayuki ; et
al. |
December 24, 2009 |
METHOD FOR MANUFACTURING DISPERSION AND LIQUID MIXING DEVICE
Abstract
In a method for manufacturing a dispersion which includes a
dispersion medium and particles dispersed therein, the method
includes bringing at least two types of liquids into contact with
each other to form a reaction product comprising the particles,
wherein the liquids are ejected from respective nozzles to be
brought into contact with each other and then to flow in an
integrated manner while forming a spiral flow.
Inventors: |
Teshima; Takayuki;
(Yokohama-shi, JP) ; Hino; Tetsuo; (Yamato-shi,
JP) ; Hanyu; Yukio; (Isehara-shi, JP) |
Correspondence
Address: |
CANON U.S.A. INC. INTELLECTUAL PROPERTY DIVISION
15975 ALTON PARKWAY
IRVINE
CA
92618-3731
US
|
Assignee: |
CANON KABUSHIKI KAISHA
Tokyo
JP
|
Family ID: |
41431886 |
Appl. No.: |
12/488587 |
Filed: |
June 22, 2009 |
Current U.S.
Class: |
523/315 ;
422/220 |
Current CPC
Class: |
B01F 5/0256
20130101 |
Class at
Publication: |
523/315 ;
422/220 |
International
Class: |
B01J 19/26 20060101
B01J019/26; B01J 13/00 20060101 B01J013/00; B01J 14/00 20060101
B01J014/00; B01F 5/08 20060101 B01F005/08 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 24, 2008 |
JP |
2008-165078 |
Oct 29, 2008 |
JP |
2008-278426 |
Claims
1. A method for manufacturing a dispersion which includes a
dispersion medium and particles dispersed therein, the method
comprising: bringing at least two types of liquids into contact
with each other to form a reaction product comprising the
particles, wherein the liquids are ejected from respective nozzles
to be brought into contact with each other and then to flow in an
integrated manner while forming a spiral flow.
2. The method for manufacturing the dispersion according to claim
1, wherein traveling directions of the ejected liquids intersect
each other in a free space.
3. The method for manufacturing the dispersion according to claim
2, wherein the nozzles are disposed so that the liquids are brought
into contact with each other in a state in which centers of axes of
the ejected liquids in the traveling directions deviate from each
other.
4. The method for manufacturing the dispersion according to claim
3, wherein the nozzles are disposed so that, in a cross-section
which is perpendicular to a liquid-contact surface between one
liquid A of the two types of liquids and another liquid B of the
two types of liquids, and which is perpendicular to a traveling
direction of an integrated liquid formed of the liquid A and the
liquid B, a gravity center Ga of the liquid A and a gravity center
Gb of the liquid B deviate from each other with respect to an
identical normal line to the liquid-contact surface.
5. The method for manufacturing the dispersion according to claim
1, wherein the liquids which flow in an integrated manner while
forming a spiral flow form a spiral-shaped interface
therebetween.
6. The method for manufacturing the dispersion according to claim
1, wherein one of the two types of liquids is a solution capable of
dissolving a pigment, and the other liquid is a solution capable of
decreasing the solubility of the pigment.
7. The method for manufacturing the dispersion according to claim
1, wherein one of the two types of liquids is a solution comprising
a coupler, and the other liquid is a solution comprising a
diazonium salt.
8. The method for manufacturing the dispersion according to claim
1, wherein at least one of the two types of liquids comprises a
dispersing agent.
9. The method for manufacturing the dispersion according to claim
1, wherein the dispersion is a starting material for an inkjet
recording ink.
10. A liquid mixing device comprising: a plurality of nozzles
ejecting at least two types of liquids, in which the liquid ejected
from the nozzles are mixed together, wherein the nozzles are
disposed so that the liquids ejected from the respective nozzles
are brought into contact with each other and are then allowed to
flow in an integrated manner while forming a spiral flow.
11. The liquid mixing device according to claim 10, wherein
travelling directions of the liquids ejected from the respective
nozzles intersect each other in a free space.
12. The liquid mixing device according to claim 11, wherein the
nozzles are disposed so that the liquids are brought into contact
with each other in a state in which centers of axes of the ejected
liquids in the traveling directions deviate from each other.
13. The liquid mixing device according to claim 10, wherein a
plurality of nozzle pairs respectively comprising the plurality of
the nozzles are integrally disposed.
14. The liquid mixing device according to claim 10, wherein the
plurality of nozzles comprise three or more nozzles.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method for manufacturing
a dispersion and a liquid mixing device.
[0003] 2. Description of the Related Art
[0004] As functional materials included in dispersions, for
example, there have been known agricultural chemicals, such as an
herbicide and a pesticide, medicine, such as an anticancer agent,
an antiallergic agent, and an antiphlogistic, and coloring
materials contained, for example, in ink, toner, and color
filters.
[0005] In addition, as the coloring materials contained in ink,
toner, and the like, pigments have started to be used. In these
situations, in order to obtain a superior pigment dispersion using
a pigment, a pigment dispersing method using a microjet reactor has
been proposed.
[0006] In US 2002/0040665 A1, a method for forming a suspension
liquid of a pigment has been disclosed in which a solution
containing a solvent and a crude pigment dissolved therein, and a
precipitation medium, are sprayed and are allowed to collide with
each other in a housing of a reactor chamber.
[0007] In addition, in US 2007/0149651 A1, a method for
manufacturing a dispersion has been disclosed which includes a step
of generating a reaction product by reaction between two types of
liquids so as to form a dispersion including the reaction product
dispersed in a dispersion medium.
[0008] In particular, in US 2007/0149651 A1, the two types of
liquids are ejected from respective nozzles which are separately
provided so that traveling directions of the liquids thus ejected
intersect each other at an angle of 120.degree. or less, and so
that these liquids then flow in an integrated manner. Accordingly,
a method for manufacturing a dispersion in which the reaction
product is generated is disclosed.
[0009] In US 2002/0040665 A1, since the solution containing the
pigment and the precipitation medium are sprayed frontally from
respective nozzles facing each other and are mixed together, a
liquid is splashed in the housing of the chamber.
[0010] In the case described above, it is supposed that the
splashed liquid and/or reaction product adheres and deposits on an
inside wall of the housing and then separates and peels off
therefrom as the time passes.
[0011] In addition, the liquid or reaction product that separates
and peels off may unfavorably cause a secondary reaction with
liquids which are newly sprayed from the nozzles.
[0012] The disclosure of US 2007/0149651 A1 may be applied to the
process of US 2002/0040665 A1, and discloses that since the splash
of the liquid is suppressed, the secondary reaction caused thereby
can be prevented, and a dispersion can be stably manufactured for a
relatively long period of time.
[0013] Although the method described in US 2007/0149651 A1 is a
contribution to this technical field, the technique described can
still be improved. For example, according to the method disclosed
in US 2007/0149651 A1, a dispersion including a reaction product
having a relatively small particle diameter can be obtained;
however, variation in the particle diameters still exists.
SUMMARY OF THE INVENTION
[0014] According to one aspect of the invention, a method for
manufacturing a dispersion which includes a dispersion medium and
particles dispersed therein is provided. The method includes
bringing at least two types of liquids into contact with each other
to form a reaction product comprising the particles, wherein the
liquids are ejected from respective nozzles to be brought into
contact with each other and then to flow in an integrated manner
while forming a spiral flow.
[0015] Further features of the present invention will become
apparent from the following description of exemplary embodiments
with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a schematic view illustrating a method according
to an embodiment of the present invention.
[0017] FIGS. 2A to 2E are schematic views each illustrating one
example of a method for generating a spiral flow according to an
embodiment of the invention.
[0018] FIG. 3 is a schematic view showing one example of a mixing
device in which two liquids are brought into contact with each
other to form a spiral flow according to an embodiment of the
invention.
[0019] FIG. 4 is a schematic view showing one example of a mixing
device in which two liquids are brought into contact with each
other to form a spiral flow according to an embodiment of the
invention.
[0020] FIG. 5 is a schematic view showing one example of a mixing
device in which two liquids are brought into contact with each
other to form a spiral flow according to an embodiment of the
invention.
[0021] FIG. 6 is a schematic view showing one system example of a
device for manufacturing a dispersion according to an embodiment of
the invention.
[0022] FIG. 7 is a schematic view showing one example of a device
in which a plurality of nozzle pairs is integrally disposed
according to an embodiment of the invention, each nozzle pair
forming a spiral flow by bringing two liquids into contact with
each other.
[0023] FIG. 8 is a schematic view showing one example of a mixing
device according to an embodiment of the invention in which three
liquids are brought into contact with each other to form a spiral
flow.
[0024] FIGS. 9A and 9B are schematic views each showing one example
of a mixing device according to an embodiment of the invention in
which two liquids are brought into contact with each other to form
a spiral flow.
[0025] FIG. 10 is a photograph showing a state in which after two
liquids are brought into contact with each other, an integrated
flow forms a spiral flow.
[0026] FIG. 11 is a photograph showing a state in which after two
liquids are brought into contact with each other, an integrated
flow does not form a spiral flow.
[0027] FIG. 12 is a photograph showing a state in which after two
liquids are brought into contact with each other, an integrated
flow does not form a spiral flow and spreads in the form of a
fan.
DESCRIPTION OF THE EMBODIMENTS
[0028] In one embodiment of the invention, a method for
manufacturing a pigment dispersion comprises a method for
manufacturing a dispersion having a dispersion medium and particles
dispersed therein. The method includes bringing at least two types
of liquids into contact with each other to form a reaction product
comprising the particles, with the particles being formed of the
reaction product. In addition, after nozzles are disposed so that
liquids ejected therefrom are brought into contact with each other
and are then allowed to flow in an integrated manner while forming
a spiral flow, the liquids are ejected from the nozzles.
[0029] According to one aspect of the present invention, a spiral
flow indicates a flow in which a plurality of liquids move in an
axial direction by circular movement around a shared axis while
being intertwined with each other.
[0030] Since a plurality of liquids circulate around the axis while
being intertwined with each other, the flows of the liquids have
improved stability, and more uniform mixing and reaction between
the liquids can be achieved. As a result, a pigment dispersion
having particles with a relatively small diameter and a narrow
particle distribution can be obtained.
[0031] Aspects of the present invention include a method in which,
after nozzles are disposed so that traveling directions of the
liquids intersect each other in a free space, and so that after
being brought into contact with each other in a free space the
liquids flow in an integrated manner while forming a spiral flow,
the liquids are ejected from the nozzles.
[0032] Aspects of the present invention also include a method in
which the nozzles are disposed so that the liquids ejected
therefrom are brought into contact with each other while the
centers of the axes of the ejected liquids in the traveling
directions deviate from each other.
[0033] Aspects if the present invention also include a method in
which the nozzles are disposed so that, in a cross-section which is
perpendicular to a liquid-contact surface between one liquid A of
two types of liquids and another liquid B of the two types of
liquids, and is perpendicular to a traveling direction of an
integrated liquid formed of the liquids A and B, a gravity center
Ga of the liquid A and a gravity center Gb of the liquid B deviate
with respect to the identical normal line to the liquid-contact
surface.
[0034] In addition, according to one aspect of the present
invention, one liquid of the two types of liquids may be a solution
that is capable of dissolving a pigment, and the other liquid may
be a solution that is capable of decreasing the solubility of the
pigment. In addition, one liquid of the two types of liquids may be
a solution comprising a coupler, and the other liquid may be a
solution comprising a diazonium salt.
[0035] Furthermore, at least one liquid of the two types of liquids
may comprise a dispersing agent.
[0036] Hereinafter, with reference to the drawings, aspects of the
present invention will be described in detail.
[0037] FIG. 1 is a schematic view showing an embodiment of a liquid
mixing device applicable to a method for manufacturing a dispersion
according to one aspect of the present invention, and also showing
a spiral flow formed by the device.
[0038] The embodiment of the liquid mixing device shown in FIG. 1
is a mixing device in which a first liquid (A) 191 and a second
liquid (B) 192 are ejected from two openings 111 and 112 of two
nozzles 121 and 122, respectively, and after the liquids are
brought into contact with each other, a spiral flow is formed. In
this figure, a case in which the traveling directions of the
liquids are controlled to intersect each other in a free space is
shown by way of example. That is, according to this example, after
the liquids intersect (i.e., are brought into contact with) each
other in a free space, the liquids are integrated with each other
to form a spiral flow 181.
[0039] The intersection performed in a free space indicates that
liquids ejected from nozzle openings are not brought into contact
with materials, such as a housing and a wall during intersection
therebetween, and instead are first brought into contact with each
other in, for example, at least one of an air space, an open space,
a reduced-pressure controlled space, and a space in which a gas
atmosphere is controlled.
[0040] According to aspects of the present invention, when the
liquid A and the liquid B are mixed together, a chemical reaction
occurs, and hence a dispersion in which particles generated thereby
is dispersed in a dispersion medium may be manufactured.
[0041] As chemical reactions according to embodiments of the
invention, for example, there may be mentioned one or more of a
coupling reaction, a hydrolysis reaction, an ion reaction, a
radical reaction, a dehydration reaction, an addition reaction, a
polycondensation reaction, an oxidation reaction, a reduction
reaction, a neutralization reaction, and an enzyme reaction.
[0042] In the above list of chemical reactions according to
embodiments of the invention, a reaction may also be included
therein in which when a solution containing a component is mixed
with another solution (such as in the case of a solvent), the
solubility of the component in the mixed solution is decreased, and
the component is precipitated.
[0043] In addition, in the above reactions according to embodiments
of the invention, a plurality of reactions which occur in
combination may also be included.
[0044] Embodiments of a method for manufacturing a dispersion
according to aspects of the present invention include a method in
which the liquids A and B are ejected from the nozzle openings 111
and 112, respectively, and are brought into contact with each other
on extended lines of the traveling directions of the liquids to
form the spiral flow 181.
[0045] An angle T at which the liquids A and B are brought into
contact with each other may be set to, for example, 150.degree. or
less.
[0046] However, the angle T may also be 120.degree. or less, to
improve the stability of the spiral flow 181, for example the angle
T may be set between 50.degree. and 10.degree..
[0047] According to aspects of the present invention, a spiral flow
indicates a flow in which a plurality of liquids moves in an axial
direction by circular movement around the shared axis while being
intertwined with each other.
[0048] According to research carried out by the inventors, since
the liquids A and B are ejected from the openings 111 and 112,
respectively, before the two liquids are brought into contact with
each other, the velocity of the liquid A at a central portion of
the traveling axis is higher than that at a peripheral portion,
which can be influenced by a nozzle wall. As for the liquid B, the
velocity at a central portion of the traveling axis is also higher,
as described above.
[0049] In addition, since the spiral flow is formed after the
liquids are brought into contact with each other, at the initial
stage after the contact, the flow of the liquid A and the flow of
the liquid B in a cross-sectional direction perpendicular to the
traveling direction of the spiral flow rotates so that the liquid A
and the liquid B rub against each other. That is, since the two
liquids both rotate, for example, in a clock-wise direction, the
liquids rotate in directions at a liquid-contact surface so that
the rotations thereof are counteracted by each other.
[0050] Subsequently, a flow of the liquid A or B, whichever is
dominant, draws the other flow, so that the two types of liquids
flow in an integrated manner while forming a spiral-shaped
interface. Since the spiral-shaped interface is formed, the contact
surface area between the liquids A and B is larger than that
obtained when the liquids are brought into contact with each other
at a flat plane interface.
[0051] As a result, the reaction between the liquids A and B occurs
in a wider area, and hence the reaction may be completed within a
shorter period of time.
[0052] In addition, the spiral-shaped interface disappears as the
time further passes (i.e., as the liquids flow), so that a state in
which the liquids are regarded as an approximately uniform mixture
(composition or dispersion) can be obtained.
[0053] For the reasons described above, according to aspects of the
present invention, it is possible to manufacture a dispersion that
is excellent in uniform particle size. In addition, since the
spiral flow 181 is formed, the flow fluxes of the liquids A and B
can be suppressed from spreading, and as a result, the effect of
being able to relatively easily recover the dispersion can be
obtained.
[0054] Next, a method for generating a spiral flow according to an
embodiment of the present invention will be described.
[0055] FIGS. 2A to 2E are schematic views each illustrating
generation of a spiral flow according to an embodiment of the
invention, and are cross-sectional views of liquids each
perpendicular to a liquid-contact surface between the liquids A and
B, and perpendicular to a traveling direction of the integrated
liquid.
[0056] According to aspects of the present invention, since the
liquids are brought into contact with each other while the centers
of the axes of the liquids thus ejected in the traveling directions
deviate from each other, the spiral flow is formed. In this case,
the centers of the axes of the liquids in the traveling directions
are represented by reference numerals 107a and 107b.
[0057] Hereinafter, the case in which the liquids are brought into
contact with each other while the centers of the axes of the two
liquids deviate from each other will be described in more
detail.
[0058] In FIGS. 2A through 2E, reference numeral 150 indicates the
liquid-contact surface, reference numeral 191 indicates a
cross-section of the liquid A, reference numeral 107a indicates a
gravity center Ga of the liquid A, reference numeral 192 indicates
a cross-section of the liquid B, and reference numeral 107b
indicates a gravity center Gb of the liquid B. In addition,
reference numeral 108 indicates the normal line (passing through
the gravity center of one of the liquids) to the liquid-contact
surface 150 (and normal, i.e. perpendicular, to the liquid-contact
surface).
[0059] In FIGS. 2A to 2E, the gravity center 107a of the liquid A
and the gravity center 107b of the liquid B deviate from each other
with respect to the identical normal line 108.
[0060] That is, according to one aspect of the present invention,
in order to form the spiral flow, it may be effective that the
gravity centers of two liquids in a cross-section perpendicular to
the liquid-contact surface between the two liquids, and
perpendicular to the traveling direction of the integrated liquid,
are disposed at positions so as to deviate from each other with
respect to the identical normal line to the liquid-contact
surface.
[0061] FIG. 2A shows the case in which the two liquids 191 and 192
have approximately circular cross-sections, although with different
diameters, and FIG. 2B shows the case in which the two liquids each
have an oval cross-section.
[0062] FIG. 2C shows the case in which the liquid 191 has a
snowman-shaped (i.e., gourd-shaped) cross-section, FIG. 2D shows
the case in which the liquid 191 has a daruma doll-shaped
cross-section, and FIG. 2E shows the case in which the two liquids
each have a snowman-shaped (i.e., gourd-shaped) cross-section.
[0063] The positional relationship between the gravity centers of
the two liquids each shown in FIGS. 2A to 2E can be measured as
described below.
[0064] As shown in the embodiment of FIG. 3, a nozzle having an
opening 112 which ejects the liquid 192 is fixed to an XY.theta.
stage 130 using a nozzle supporting member 136 and a nozzle fixing
member 138.
[0065] As shown in the embodiment of FIG. 4, when a knob of the
XY.theta. stage 130 is controlled, only the liquid 191 is ejected
from the opening 111, and the gravity center can be calculated
using cameras 145 and 146. Next, as shown in the embodiment of FIG.
5, only the other liquid 192 is ejected, and the gravity center may
be calculated in a manner similar to that described above.
[0066] In addition, since the surface tension and viscosity of
liquids may also be factors in forming a stable spiral flow, for
example, the angle at which the two liquids are brought into
contact with each other and the ejection pressures thereof may be
adjusted, for example in accordance with liquids to be handled.
[0067] With reference to FIGS. 1 to 5, an embodiment of a method
for manufacturing a dispersion has been described in which two
types of liquids are ejected from two nozzles; however, instead of
increasing the size of a reaction chamber, the production volume
may also be increased by increasing the number of nozzles, so that
mass production can also be realized.
[0068] A device shown in the embodiment of FIG. 7 is a device in
which a plurality of nozzle pairs are integrally disposed, each
nozzle pair having the nozzle 121 ejecting the first liquid A and
the nozzle 122 ejecting the second liquid B. By this device, a
reaction can also be performed in each pair by generating the
spiral flow 181.
[0069] Heretofore, the method in which two types of liquids are
used has been described; however, three or more types of liquid may
also be used.
[0070] A device shown in the embodiment of FIG. 8 is a device to
form the spiral flow 181 using three types of liquids. In this
device, in addition to the first liquid (A) 191 and the second
liquid (B) 192, a third liquid (C) 193 is ejected from a third
ejection opening 113 to form the spiral flow 181. As shown in FIG.
8, three or more nozzles might optionally be used as an example of
the embodiment according to the present invention.
[0071] In the case of this device, although all the three liquids
may be different from each other, the liquids may also be
appropriately changed in accordance with a predetermined
dispersion, and for example, the same liquid may be used for two of
the three liquids, or the concentration of the liquid may be
changed while the components of the liquid are not changed.
[0072] Next, besides the nozzle portions ejecting liquids, an
apparatus for manufacturing a dispersion according to an embodiment
of the present invention will be described as a system example.
[0073] FIG. 6 is a schematic view showing one system example
according to an embodiment of the invention.
[0074] In the embodiment as shown in FIG. 6, reference numeral 100
indicates a mixing device including the nozzles 121 and 122.
Liquids ejected from the nozzles 121 and 122 are brought into
contact with each other for mixing and are then recovered by a
mixed liquid recovering unit 108.
[0075] In FIG. 6, reference numerals 131 and 132 each indicate a
liquid supply unit, and liquids are supplied to the liquid supply
units 131 and 132 from liquid storage tanks. As the liquid supply
units 131 and 132, a commercially available syringe pump, plunger
pump, diaphragm pump, electromagnetic pump, or the like may be
used.
[0076] Monitoring units 141 and 142, control units 151 and 152, and
temperature control units 161 and 162 are connected between the
mixing device 100 and the liquid supply units 131 and 132 through
pipes 171 and 172, respectively.
[0077] The monitoring units 141 and 142 each comprise at least one
of a flowmeter, a pressure gauge, and the like, and the control
units 151 and 152 each comprise at least one of a valve, a bulb,
and the like. The temperature control units 161 and 162 each may
comprise at least one of a heater, cooler, and the like.
[0078] In order to connect the units described above, pipes 171 and
172 may be used, which are each formed of a tube or the like having
resistance against the liquid to be transported. The individual
units disposed between the liquid mixing device 100 and the liquid
supply units 131 and 132 may be provided as shown, and optionally,
all of the units may not always be provided in some cases.
[0079] Transportation of the liquids ejected from the nozzles 121
and 122 to the mixed liquid recovery unit 108 may be performed
using the flow of the liquid generated by its own gravity, or by
using a pressure generated by, for example, a pump.
[0080] As the liquid mixing device 100 shown in the embodiment of
FIG. 6, one or more of the devices described, for example, with
reference to FIGS. 1, 3, and 8, may be used. The liquid mixing
device 100 may be formed from a small chemical device used to mix
liquids or to perform a reaction therebetween.
[0081] The shape of a nozzle opening which forms an ejection port
for ejecting a liquid may be, for example, a circle, an oval, a
polygonal shape, such as a regular tetragon, an axial symmetric
shape, such as a rectangle, or a non-axial symmetric shape
integrally formed from different shapes.
[0082] Immediately after being ejected the liquid has a shape
similar to the opening shape; however, the cross-sectional shape
gradually changes to a circle or an oval due to the surface tension
of the liquid.
[0083] The shapes of the nozzle openings ejecting the liquids A and
B may be the same or may be different from each other. In addition,
the nozzle opening areas for the two types of liquids may be the
same or may be different from each other.
[0084] As materials used for the nozzle openings applicable to the
present invention, for example, at least one of metal, glass,
silicon, Teflon.RTM. (registered trade name), ceramic, and plastic
may be provided.
[0085] For example, to provide one or more of heat resistance,
pressure resistance, and solvent resistance, one or more of metal,
glass, silicon, Teflon.RTM. (registered trade name), and ceramic
may be used; in one version, a metal material may be used.
[0086] As the metal material, for example, at least one of
stainless steel, Hastelloy (Ni--Fe alloy) nickel, gold, platinum,
and tantalum may be provided.
[0087] In addition, in order to obtain corrosion resistance of the
nozzle and/or a predetermined surface energy, a nozzle having a
surface processed by lining may also be used.
[0088] The method for manufacturing a dispersion according to
aspects of the present invention includes an embodiment in which
the liquids A and B are brought into contact with each other in a
free space to form a spiral flow. By the method described above,
since the liquids A and B form a spiral flow and are mixed together
at the same timing, the uniformity of reaction and mixing is
improved, and hence the diameters of particles to be formed are
more likely to coincide with each other.
[0089] In addition, when the opening areas of the nozzle openings
are decreased, since the absolute volumes of the liquids to be
supplied are decreased, rapid mixing and reaction occur, and as a
result, the diameters of particles are more likely to decrease.
[0090] The reason the diameters of particles are more likely to
decrease when rapid mixing is performed is that, since a great
number of nuclei are generated by instantaneous mixing, and a great
number of particles are generated thereby, particle formation
occurs relatively smoothly, and particles having a relatively small
primary particle diameter are formed.
[0091] The opening area of the opening per one nozzle supplying the
liquid may be 7 mm.sup.2 or less in view of mixing efficiency, for
example such as 0.8 mm.sup.2 or less, and even 0.2 mm.sup.2 or
less, such as 0.008 mm.sup.2 or less.
[0092] In addition, when the ejection from the nozzle opening and
the viscosity of the liquid are taken into consideration, the above
opening area may be 0.00008 mm.sup.2 or more, such as 0.002
mm.sup.2 or more.
[0093] As the opening area of the nozzle opening is decreased, the
liquid width (i.e., liquid diameter) of the liquid to be supplied
decreases, and as a result, the mixing may be more efficiently
performed.
[0094] On the other hand, as the opening area of the opening is
increased, the liquid width also increases, and as a result, the
mixing efficiency may be degraded.
[0095] However, when a liquid having a relatively high viscosity is
used, and when an opening having a smaller opening area is used,
ejection may not be adequately performed in some cases due to a
large pressure loss; hence, it may be effective to select the
opening area of the opening in accordance with a liquid to be
used.
[0096] According to aspects of the present invention, when the
liquid A and the liquid B are not brought into contact with each
other in a structurally defined flow path (e.g., a flow path
defined by walls) but instead in a free space, the flow path does
not become clogged with particles formed by the contact between the
liquids.
[0097] In addition, as the mixing is not mixing (e.g., reaction) in
a flow path caused by self-dispersion during a laminar flow
process, inhibition of mixing caused by particles to be formed is
suppressed, and hence a particle generation concentration can be
increased.
[0098] Accordingly, the amount of a solvent or the like to be used
can be decreased, and the times for subsequent condensation and
purification steps can also be decreased; hence, the cost of the
dispersion manufacturing process can be decreased.
[0099] In a case where a pigment can be dissolved only at a low
concentration, in order to generate an organic metal complex, the
amount of a solvent may be increased, and condensation may be
performed by ultrafiltration or reduced-pressure distillation;
however, certain inconveniences, such as the cost generated for
waste liquid treatment and/or load placed on the environment, may
occur.
[0100] In the case described above, embodiments of the present
invention may be particularly effective.
[0101] As examples of particle dispersions manufactured by the
method for manufacturing a dispersion according to aspects of the
present invention, for example, one or more of inorganic particles,
organic particles, emulsion or polymer particles, and composite
particles thereof may be mentioned.
[0102] In addition, the diameter of particles may be determined
from the order of nanometers to millimeters in accordance with
material properties and applications.
[0103] The emulsion or polymer particles may be used for
manufacturing, for example, a general latex.
[0104] The inorganic particles may be used for manufacturing, for
example, general metal particles, and in a hydrolysis
polycondensation reaction, for example, a combination between the
liquid A as an inorganic alkoxide and the liquid B as a solution
containing water may be mentioned by way of example.
[0105] In this case, the reaction product may be an
inorganic-alkoxide hydrolysis polycondensate.
[0106] Hydrolysis of an inorganic alkoxide and a subsequent
polycondensation reaction are reactions collectively referred to as
a sol-gel method. This is a method in which an inorganic alkoxide
is processed in a solution by a hydrolysis polycondensation
reaction to form a sol in which fine particles of one or more of an
inorganic oxide and an inorganic hydroxide is dissolved, and the
reaction is further advanced to form a gel.
[0107] According to one aspect, in order to obtain a dispersion of
an inorganic-alkoxide hydrolysis polycondensate, a dispersing agent
may be added to at least one of the liquids A and B.
[0108] However, when an inorganic-alkoxide hydrolysis
polycondensate as a reaction product has sufficient dispersion
properties to disperse in a dispersion medium, a dispersing agent
may not necessarily be contained in one of the liquids A and B, or
in both of them.
[0109] As the inorganic alkoxide, for example, a compound
represented by the following formula (I) may be mentioned.
R.sup.1.sub.nM(OR.sup.2).sub.m-n (I)
In the formula (I), M represents an atom selected from Si, Al, Ti,
Zr, Ca, Fe, V, Sn, Li, and Be, R.sup.2 represents an alkyl group,
R.sup.1 represents an alkyl group or an alkyl group having a
functional group, m represents the atomic valence of M, and n
represents an integer from 1 to m.
[0110] Among the compounds represented by the formula (I), a
compound may be provided in which n=0 is satisfied, that is, in
which only at least one alkoxy group is bonded to M.
[0111] When M represents Ti, since the atomic valence m of Ti is 4,
the alkoxide is represented by Ti(OR.sup.2).sub.4.
[0112] As the titanium alkoxide described above, for example, at
least one of Ti(OCH.sub.3).sub.4, Ti(OC.sub.2H.sub.5).sub.4,
Ti(OC.sub.3H.sub.7).sub.4, Ti(OCH(CH.sub.3).sub.2).sub.4, and
Ti(OC.sub.4H ).sub.4 may be provided; however, the titanium
alkoxide is not limited thereto.
[0113] When M represents Si, since the atomic valence m of Si is 4,
the alkoxide is represented by Si(OR.sup.2).sub.4.
[0114] As the alkoxysilane described above, for example, at least
one of Si(OCH.sub.3).sub.4, Si(OC.sub.2H.sub.5).sub.4,
H.sub.2NCH.sub.2Si(OCH.sub.3).sub.3,
H.sub.2NCH.sub.2SiCH.sub.3(OCH.sub.3).sub.2,
H.sub.2NCH.sub.2CH.sub.2Si(OCH.sub.3).sub.3,
H.sub.2NCH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.2CH.sub.3).sub.3,
HN(CH.sub.3)CH.sub.2Si(OCH.sub.3).sub.3,
HN(CH.sub.3)CH.sub.2CH.sub.2Si(OCH.sub.3).sub.3,
HN(CH.sub.3)CH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.3).sub.3,
HN(CH.sub.3)CH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.2CH.sub.3).sub.3,
N(CH.sub.3).sub.2CH.sub.2Si(OCH.sub.3).sub.3,
N(CH.sub.3).sub.2CH.sub.2CH.sub.2Si(OCH.sub.3).sub.3,
N(CH.sub.3).sub.2CH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.2CH.sub.3).sub.3,
Cl.sup.-N.sup.+(CH.sub.3).sub.3CH.sub.2Si(OCH.sub.3).sub.3,
Cl.sup.-N.sup.+(CH.sub.3).sub.3CH.sub.2CH.sub.2Si(OCH.sub.3).sub.3,
Cl.sup.-N.sup.+(CH.sub.3).sub.3CH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.3).sub.-
3,
Cl.sup.-N.sup.+(CH.sub.3).sub.3CH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.3).su-
b.3,
Cl.sup.-N.sup.+(CH.sub.3).sub.3CH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.2CH-
.sub.3).sub.3,
C.sub.6H.sub.5NCH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.3).sub.3,
NH.sub.2CONHCH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.3).sub.3, and
NH.sub.2CH.sub.2CH.sub.2NHCH.sub.2CH.sub.2CH.sub.2Si(OCH.sub.3).sub.3
may be provided.
[0115] When M represents Al, since the atomic valence m of Al is 3,
the alkoxide is represented by Al(OR.sup.2).sub.3.
[0116] As the aluminum alkoxide described above, for example, at
least one of Al(OCH.sub.3).sub.3, Al(OC.sub.2H.sub.5).sub.3,
Al(OC.sub.3H.sub.7).sub.3, Al(OCH(CH.sub.3).sub.2).sub.3, and
Al(OC.sub.4H.sub.9).sub.3 may be provided.
[0117] As other inorganic alkoxides, for example, at least one of
Ca(OC.sub.2H.sub.5).sub.2, Fe(OC.sub.2H.sub.5).sub.3,
V(OCH(CH.sub.3).sub.2).sub.4, Sn(OC(CH.sub.3).sub.3).sub.4,
Li(OC.sub.2H.sub.5), and Be(OC.sub.3H.sub.7).sub.2 may be
provided.
[0118] In addition, instead of the alkoxide, an inorganic halide in
which OR.sup.2 represents a halogen atom may also be used.
[0119] According to aspects of the present invention, the reaction
is not limited to those described above, and the method for
manufacturing a dispersion according to embodiments of the present
invention may also be used for manufacturing other dispersions,
including metal nanoparticles and the like.
[0120] As the organic particles, coloring materials, such as
pigments or dyes, may be provided.
[0121] As usable dyes, for example, there may be provided one or
more of water-soluble dyes, such as a direct dye, an acid dye, a
basic dye, a reactive dye, and a food colorant; lipid-soluble dyes;
and water-insoluble colorants, such as a disperse dye.
[0122] For example, one or more of C. I. Solvent Blue, -33, -38,
-42, -45, -53, -65, -67, -70, -104, -114, -115, and -135; C. I.
Solvent Red, -25, -31, -86, -92, -97, -118, -132, -160, -186, -187,
and -219; C. I. Solvent Yellow, -1, -49, -62, -74, -79, -82, -83,
-89, -90, -120, -121, -151, -153 and -154, may be provided.
[0123] As the water-soluble dyes, for example, one or more of C. I.
Direct Black, -17, -19, -22, -32, -38, -51, -62, -71, -108, -146,
and -154; C. I. Direct Yellow, -12, -24, -26, -44, -86, -87, -98,
-100, -130, and -142; C. I. Direct Red, -1, -4, -13, -17, -23, -28,
-31, -62, -79, -81, -83, -89, -227, -240, -242, and -243; C. I.
Direct Blue, -6, -22, -25, -71, -78, -86, -90, -106, and -199; C.
I. Direct Orange, -34, -39, -44, -46, and -60; C. I. Direct Violet,
-47 and -48; C. I. Direct Brown, -109; C. I. Direct Green, direct
dyes such as -59; C. I. Acid Black, -2, -7, -24, -26, -31, -52,
-63, -112, -118, -168, -172, and -208; C. I. Acid Yellow, -11, -17,
-23, -25, -29, -42, -49, -61, and -71; C. I. Acid Red, -1, -6, -8,
-32, -37, -51, -52, -80, -85, -87, -92, -94, -115, -180, -254,
-256, -289, -315, and -317; C. I. Acid Blue, -9, -22, -40, -59,
-93, -102, -104, -113, -117, -120, -167, -229, -234, and -254; C.
I. Acid Orange, -7, -19; C. I. Acid Violet, acid dyes such as -49;
C. I. Reactive Black, -1, -5, -8, -13, -14, -23, -31, -34, and -39;
C. I. Reactive Yellow, -2, -3, -13, -15, -17, -18, -23, -24, -37,
-42, -57, -58, -64, -75, -76, -77, -79, -81, -84, -85, -87, -88,
-91, -92, -93, -95, -102, -111, -115, -116, -130, -131, -132, -133,
-135, -137, -139, -140, -142, -143, -144, -145, -146, -147, -148,
-151, -162, and -163; C. I. Reactive Red, -3, -13, -16, -21, -22,
-23, -24, -29, -31, -33, -35, -45, -49, -55, -63, -85, -106, -109,
-111, -112, -113, -114, -118, -126, -128, -130, -131, -141, -151,
-170, -171, -174, -176, -177, -183, -184, -186, -187, -188, -190,
-193, -194, -195, -196, -200, -201, -202, -204, -206, -218, and
-221; C. I. Reactive Blue, -2, -3, -5, -8, -10, -13, -14, -15, -18,
-19, -21, -25, -27, -28, -38, -39, -40, -41, -49, -52, -63, -71,
-72, -74, -75, -77, -78, -79, -89, -100, -101, -104, -105, -119,
-122, -147, -158, -160, -162, -166, -169, -170, -171, -172, -173,
-174, -176, -179, -184, -190, -191, -194, -195, -198, -204, -211,
-216, and -217; C. I. Reactive Orange, -5, -7, -11, -12, -13, -15,
-16, -35, -45, -46, -56, -62, -70, -72, -74, -82, -84, -87, -91,
-92, -93, -95, -97, and -99; C. I. Reactive Violet, -1, -4, -5, -6,
-22, -24, -33, -36, and -38; C. I. Reactive Green, -5, -8, -12,
-15, -19, and -23; C. I. Reactive Brown, reactive dyes, such as -2,
-7, -8, -9, -11, -16, -17, -18, -21, -24, -26, -31, -32, and -33;
C. I. Basic Black, -2; C. I. Basic Red, -1, -2, -9, -12, -13, -14,
and -27; C. I. Basic Blue, -1, -3, -5, -7, -9, -24, -25, -26, -28,
and -29; C. I. Basic Violet, -7, -14, and -27; and C. I. Food
Black, -1 and -2, may be provided.
[0124] As the pigments, one or more of an inorganic pigment, an
organic pigment, and a composite pigment thereof may be
provided.
[0125] As the inorganic pigment, one or more of the above inorganic
particles may be provided, and as the organic pigment, the
following may be provided by way of example.
[0126] As cyan pigments, for example, one or more of C. I. Pigment
Blue-1, C. I. Pigment Blue-2, C. I. Pigment Blue-3, C. I. Pigment
Blue-15, C. I. Pigment Blue-15:2, C. I. Pigment Blue-15:3, C. I.
Pigment Blue-15:4, C. I. Pigment Blue-16, C. I. Pigment Blue-22,
and C. I. Pigment Blue-60 may be provided.
[0127] As magenta pigments, for example, one or more of C. I.
Pigment Red-5, C. I. Pigment Red-7, C. I. Pigment Red-12, C. I.
Pigment Red-48, C. I. Pigment Red-48:1, C. I. Pigment Red-57, C. I.
Pigment Red-112, C. I. Pigment Red-122, C. I. Pigment Red-123, C.
I. Pigment Red-146, C. I. Pigment Red-168, C. I. Pigment Red-184,
C. I. Pigment Red-202, and C. I. Pigment Red-207, may be
provided.
[0128] As yellow pigments, for example, one or more of C. I.
Pigment Yellow-12, C. I. Pigment Yellow-13, C. I. Pigment
Yellow-14, C. I. Pigment Yellow-16, C. I. Pigment Yellow-17, C. I.
Pigment Yellow-74, C. I. Pigment Yellow-83, C. I. Pigment
Yellow-93, C. I. Pigment Yellow-95, C. I. Pigment Yellow-97, C. I.
Pigment Yellow-98, C. I. Pigment Yellow-114, C. I. Pigment
Yellow-128, C. I. Pigment Yellow-129, C. I. Pigment Yellow-151 and
C. I. Pigment Yellow-154, may be provided.
[0129] According to one embodiment of a method according to the
present invention, the liquid A may be a solution in which a
pigment is dissolved in an acidic or an alkaline solvent, or in a
mixed solvent containing an organic solvent and an acidic or an
alkaline solvent, and the liquid B may be a pigment precipitation
medium (i.e., a poor solvent that decreases a pigment
solubility).
[0130] In the case described above, the acid to be used may be
selected from acids that are each capable of dissolving a pigment
by itself or in a mixed solution with an organic solvent, and for
example, there may be used one or more of an alkylsulfonic acid,
such as methanesulfonic acid, ethanesulfonic acid, propanesulfonic
acid, or butanesulfonic acid, a halogenated alkylsulfonic acid
obtained by halogenation of the above compound, p-toluenesulfonic
acid, 2-naphthalenesulfonic acid, p-chlorobenezen sulfonic acid,
p-xylene-2-sulfonic acid, trifluoroacetic acid,
trifluoromethanesulfonic acid, sulfuric acid, hydrochloric acid,
acetic acid, phosphoric acid, and polyphosphoric acid.
[0131] In addition, the acids mentioned above may be used alone or
in combination.
[0132] For dissolution, if the acids mentioned above are solid at
room temperature, heating may be performed to its melting point or
more for fusion. In addition, the pigment may be dissolved at room
temperature or by heating.
[0133] The alkali may be selected from compounds which can dissolve
a pigment by itself, or in a mixed solution with an organic
solvent.
[0134] For example, hydroxides of alkali metals, alkoxides thereof,
hydroxides of alkali earth metals, alkoxides thereof, and organic
strong bases may be used, because of their high ability in
dissolving an organic pigment.
[0135] In particular, for example, one or more of lithium
hydroxide, sodium hydroxide, potassium hydroxide, calcium
hydroxide, potassium-tert-butoxide, potassium methoxide, potassium
ethoxide, sodium methoxide, sodium ethoxide, a quaternary ammonium
compound such as tetrabutylammonium hydroxide,
1,8-diazabicyclo[5,4,0]-7-undecene,
1,8-diazabicyclo[4,3,0]-7-nonene, and guanidine may be
provided.
[0136] In addition, the alkalis mentioned above may be used alone
or in combination.
[0137] The organic solvent (i.e., dispersion medium) may be
selected from compounds which are capable of dissolving a pigment
either by itself or by a mixed solution with an acid or an
alkali.
[0138] For example, one or more of dimethylformamide, dimethyl
sulfoxide, dimethylimidazolidinone, sulfolane, N-methylpyrrolidone,
acetonitrile, acetone, dioxane, tetramethylurea, hexamethyl
phosphoramide, hexamethyl phosphortriamide, pyridine,
propionitrile, butanone, cyclohexanone, tetrahydrofuran,
tetrahydropyrane, ethylene glycol diacetate, .gamma.-butyrolactone,
and acetic acid may be provided, and may be used in
combination.
[0139] The precipitation medium (i.e., dispersion medium) may be
selected from media which are capable of decreasing the solubility
of a dissolved pigment.
[0140] For example, one or more of water, an aqueous acidic
solution, an aqueous alkaline solution, an alcohol, an aqueous
organic solvent, a nonaqueous organic solvent, and a mixture
thereof, may be provided.
[0141] According to one embodiment, when a pigment solution, which
is the liquid A, and a precipitation medium, which is the liquid B,
are brought into contact with each other in the presence of a
dispersing agent, since dispersion properties can be imparted to
the pigment by the dispersing agent before the pigment grows into
large and coarse particles due to its precipitation, a pigment
dispersion having a relatively small particle diameter can be
effectively obtained.
[0142] According to one embodiment of a method according to the
present invention, a coupler solution may be used as the liquid A,
and a diazonium salt solution may be used as the liquid B.
[0143] When the above solutions are used, an azo compound can be
manufactured. As the azo compounds, for example, at least one of
azo-based pigments, such as a known azo, bisazo, insoluble azo
pigment, condensed azo pigment, azo lake, and chelate azo pigment,
may be manufactured. As the pigment, a commercially available
pigment may also be used. The commercially available pigments will
be mentioned below by way of example.
[0144] That is, for example, there may be mentioned one or more of
C. I. Pigment Yellow 74, 93, 94, 95, 120, 128, 151, 154, 166, 175,
180, and 181; C. I. Pigment Red 5, 31, 144, 146, 147, 150, 166,
176, 184, and 269; and C. I. Pigment Orange 31.
[0145] As the diazonium salt, for example, a diazonium salt derived
from a compound having an aromatic amine or a heterocyclic amine
structure may be used.
[0146] As the coupler, for example, at least one of a coupler
including an aromatic compound having an aniline, a phenol or a
naphthol structure, and a compound having an acetoacetoxy group,
may be used.
[0147] According to one embodiment, when the coupler solution and
the diazonium salt are brought into contact with each other in the
presence of a dispersing agent, if the azo compound is in the form
of particles, dispersion properties can be imparted to the azo
compound by the dispersing agent before the azo compound grows into
large and coarse particles due to its precipitation; hence, an
azo-compound dispersion having a relatively small particle diameter
can be effectively obtained.
[0148] When the reaction product is in the form of particles, a
dispersing agent which suppresses the particles from growing into
large and coarse particles caused by adsorption between the
particles and which suppresses cohesion therebetween may be used.
As the dispersing agent described above, for example, a surfactant
may be used. As the surfactant, for example, at least one of an
anionic, a nonionic, an amphoteric, and a cationic surfactant may
be mentioned.
[0149] According to one aspect of the present invention, when a
dispersing agent is contained in at least one of the liquids A and
B, the liquid A and liquid B can be brought into contact with each
other in the presence of the dispersing agent.
[0150] As the anionic surfactant usable in the present invention,
for example, one or more of fatty acid salts, alkylsulfate salts,
alkylarylsulfonic acid salts, alkyldiaryl ether disulfonic acid
salts, dialkyl sulfosuccinic acid salts, alkylphosphoric acid
salts, naphthalenesulfonic acid-formalin condensates,
polyoxyethylene alkylphosphoric acid ester salts, and glycerol
borate fatty acid esters, may be provided.
[0151] As the cationic surfactant, for example, one or more of
alkylamine salts, quaternary ammonium salts, alkylpyridinium salts,
and alkylimidazolium salts may be provided.
[0152] As the amphoteric surfactant, for example, one or more of
alkylbetaines, alkylamine oxides, phosphatidylcholine, and
amphiphilic block copolymers may be provided.
[0153] As the nonionic surfactant, for example, one or more of
polyoxyethylene alkyl ethers, polyoxyethylene oxypropylene block
copolymers, sorbitan fatty acid esters, glycerin fatty acid esters,
polyoxyethylene fatty acid esters, and polyoxyethylene alkylamines
may be provided.
[0154] Hereinafter, with reference to concrete examples, the
present invention will be described in more detail.
EXAMPLES
Example 1
[0155] In this example, a 2,9-dimethyl quinacridone pigment was
used.
[0156] Into an eggplant-type flask having a volume of 300 ml, 10
parts by weight of 2,9-dimethyl quinacridone was charged, and 80
parts by weight of methanesulfonic acid was further added at room
temperature. This eggplant-type flask was placed in an oil bath
heated to 80.degree. C, and stirring was performed in an argon
atmosphere for 10 minutes while heating was performed. As a result,
a quinacridone pigment solution having a violet-blue color and
containing 2,9-dimethyl quinacridone was prepared.
[0157] Next, a solution in which 6.86 parts by weight of
polyoxyethylene cetyl ether functioning as a nonionic surfactant
was dissolved in 30 parts by weight of acetonitrile was added to 50
ml of the quinacridone pigment solution to prepare the liquid A. As
the liquid B, an aqueous polyoxyethylene lauryl ether solution at a
concentration of 0.1 percent by weight was prepared.
[0158] In this example, for the contact and the mixing between the
liquid A and the liquid B, a mixing device made of Teflon.RTM.
(registered trade name) in which two nozzles were integrally
provided as shown in FIG. 9A was used. FIG. 9b is a schematic view
of nozzle openings when viewed along A and B directions shown in
FIG. 9A.
[0159] A nozzle opening 111 ejecting the liquid A had a circular
shape having a diameter of 0.25 mm. On the other hand, a nozzle
opening 112 ejecting the liquid B had a shape in which circles
having a diameter of 0.2 mm and a diameter of 0.18 mm were partly
overlapped. The distance between the centers of the two openings
having a diameter of 0.2 mm and a diameter of 0.18 mm was 0.2 mm.
The angle at which the liquids A and B were brought into contact
with each other was 45.degree.. In this mixing device, it was
designed in advance that the gravity center of the liquid A and
that of the liquid B in their cross-sections were not located on
the identical normal line to a liquid-contact surface between the
two liquids.
[0160] The liquid A was supplied by a syringe pump at a flow rate
of 5 ml/min, and the liquid B was supplied by a plunger pump at a
flow rate of 8 ml/min. After the liquids A and B were brought into
contact with each other, the two liquids were integrated together
to form a spiral flow. As a result, particles of 2,9-dimethyl
quinacridone were generated and dispersed instantaneously, so that
a magenta-colored dispersion was obtained at a high
concentration.
[0161] In addition, the generation of droplets was suppressed
because of the formation of the spiral flow, and hence no recovery
loss of the dispersion of 2,9-dimethyl quinacridone occurred.
[0162] The dispersion thus obtained was purified and condensed by
ultrafiltration. Since the dispersion having a high concentration
was obtained from the beginning, the purification and condensation
could be performed in a relatively short period of time. When the
average particle diameter of the pigment fine particles was
measured using DLS-8000 (Otsuka Electronics Co., Ltd.), the
dispersion thus obtained had very uniform particle diameters, and
the average particle diameter and the standard deviation were 89 nm
and 27 nm, respectively. Even when the quinacridone pigment thus
obtained was left for 28 days, no precipitation occurred.
[0163] A dispersion in which the quinacridone pigment thus obtained
was dispersed as a color pigment (C. I. Pigment Red-122) was used
as a starting material of an inkjet recording ink.
[0164] When the above dispersion was filled as ink in an ink tank
of BJ printer BJ F900 (manufactured by Canon Kabushiki Kaisha),
clear characters could be printed on standard paper.
Example 2
[0165] In this example, a mixing device shown in FIG. 10 was used.
In this device, the nozzle opening 111 ejecting the liquid A was
made of Teflon.RTM. (registered trade name) and had an opening
diameter of 300 .mu.m. The nozzle opening 112 ejecting the liquid B
was made of glass and had an opening diameter of 470 .mu.m. The
angle at which the liquids A and B were brought into contact with
each other was 40.degree.. The liquid A was prepared as described
below.
[0166] Dimethyl sulfoxide in an amount of 100 parts by weight was
added to 10 parts by weight of a quinacridone pigment, C. I.
Pigment Red 122, to form a suspension.
[0167] Next, 40 parts by weight of lauryl sulfate sodium was added
as a dispersing agent, and an aqueous potassium solution at a
concentration of 25% was added until lauryl sulfate sodium was
dissolved, so that the liquid A was prepared. As a liquid to be
ejected from the other nozzle opening 112, ion-exchanged water was
used.
[0168] The liquid A was supplied at a flow rate of 7 ml/min by a
syringe pump used as a liquid supply unit, and the liquid B was
supplied at a flow rate of 10 ml/min by a syringe pump.
[0169] The nozzles were placed so that the two types of liquids
ejected from the nozzles intersect on extended lines of the
respective traveling directions and so that a cross-sectional
center (gravity center) of the liquid B and a cross-sectional
center (gravity center) of the liquid A deviated with respect to
the identical normal line to the liquid-contact surface. In this
example, the placement of the nozzles was performed by a method
similar to that described with reference to FIGS. 3 to 5.
[0170] As shown in FIG. 10, after the two types of liquids were
brought into contact with each other, a spiral flow 181 was formed.
After the two types of liquids were brought into contact with each
other, a precipitation reaction and dispersing occurred
instantaneously, so that a dispersion of the quinacridone pigment
was obtained.
[0171] When the dispersion thus obtained was measured by a method
similar to that of Example 1, the particles had an average particle
diameter of 30 nm, and the particle distribution had a standard
deviation of 12 nm.
Comparative Example 1
[0172] In this comparative example, a dispersion was manufactured
under conditions similar to those of Example 2 except that the
nozzles were disposed so that after the liquids A and B were
brought into contact with each other, the spiral flow was not
formed.
[0173] In particular, after the nozzles were placed so that the two
types of liquids ejected from the nozzles were brought into contact
with each other at the centers (i.e., gravity centers) of the
liquids and on the extended lines of the respective traveling
directions, the two liquids were brought into contact with each
other and were allowed to react with each other.
[0174] After the two types of liquids were brought into contact
with each other, as shown in FIG. 11, the liquids flowed in an
integrated manner without forming a spiral flow.
[0175] When the quinacridone pigment dispersion thus obtained was
measured by a method similar to that of Example 1, the average
particle diameter of the dispersion was 30 nm, and the standard
deviation was 20 nm.
Comparative Example 2
[0176] In this comparative example, after the liquids A and B were
brought into contact with each other, the liquids were recovered by
a recovery unit while no spiral flow was formed. In particular, a
liquid mixing device was used in which a nozzle opening ejecting
the liquid A was made of Teflon.RTM. (registered trade name) and
had an opening diameter of 400 .mu.m, and a nozzle opening ejecting
the liquid B was made of glass and had an opening diameter of 470
.mu.m. The angle at which the liquids A and B were brought into
contact with each other was 100.degree.. The liquid A was prepared
as described below.
[0177] Dimethyl sulfoxide in an amount of 100 parts by weight was
added to 10 parts by weight of a quinacridone pigment, C. I.
Pigment Red 122, to form a suspension.
[0178] Next, 40 parts by weight of lauryl sulfate sodium was added
as a dispersing agent, and an aqueous sodium potassium solution at
a concentration of 25% was added until lauryl sulfate sodium was
dissolved, so that the liquid A was prepared.
[0179] As the liquid B, ion-exchanged water was used.
[0180] The liquid A was supplied at a flow rate of 18 ml/min by a
syringe pump used as a liquid supply unit, and the liquid B was
supplied at a flow rate of 20 ml/min by a syringe pump.
[0181] The nozzles were placed so that the two types of liquids
ejected from the nozzles were brought into contact with each other
at the centers thereof and on the extended lines of the respective
traveling directions. After the two liquids were brought into
contact with each other, as shown in FIG. 12, the liquids were
spread in the form of a fan, and droplets thereof were splashed
around. After the liquids were brought into contact with each
other, a re-precipitation reaction and dispersing occurred, and a
dispersion of the quinacridone pigment was obtained. When the
dispersion was recovered using a wide-mouth recovery container so
as not to lose the droplets, the dispersion had a distribution in
which two peaks were present at particle diameters of 40 to 120
nm.
Example 3
[0182] In this example, a mixing device (nozzles) similar to that
of Example 2 was used.
[0183] In particular, a nozzle ejecting the liquid A was made of
Teflon.RTM. (registered trade name) and had an opening diameter of
300 .mu.m, and a nozzle ejecting the liquid B was made of glass and
had an opening diameter of 470 .mu.m.
[0184] The angle formed between the traveling directions of the
liquids A and B was 50.degree..
[0185] As the liquid A, an aqueous 3,3'-dichlorobenzidene tetraazo
solution was used, and as the liquid B, a solution in which
polyoxyethylene lauryl ether was dissolved in an aqueous coupler
solution at a concentration of 6% was used.
[0186] The liquid A was supplied at a flow rate of 7 ml/min by a
syringe pump used as a liquid supply unit, and the liquid B was
supplied at a flow rate of 10 ml/min by a syringe pump.
[0187] In a manner similar to that of Example 2, the nozzles were
disposed, and the two liquids were allowed to flow, so that a
spiral flow was formed.
[0188] By the contact between the liquid A and the liquid B, an azo
coupling reaction occurred, and particles of Pigment Yellow 83 were
generated.
[0189] In this step, the coexistent polyoxyethylene lauryl ether
functioned as a dispersing agent, and as a result, a dispersion of
Pigment Yellow 83 was obtained in which the sizes of particles were
small and uniform. The average particle diameter of the dispersion
thus obtained was 45 nm, and the particle diameters thereof were
very uniform.
Example 4
[0190] In this example, a mixing device similar to that of Example
1 was used.
[0191] The contact and the reaction between two liquids were
performed in a manner similar to that of Example 1 except that
tetraisopropoxide titanate was used as the liquid A and an aqueous
isopropyl alcohol solution at a concentration of approximately 60%
was used as the liquid B.
[0192] As a result, a dispersion of titania was obtained as a
hydrolysis polycondensate, the average particle diameter of the
dispersion thus obtained was 30 nm, and the particle diameters
thereof were very uniform.
Example 5
[0193] In this example, a dispersion of a lipid-soluble dye was
manufactured.
[0194] A mixing device was used in which a nozzle opening ejecting
the liquid A was made of Teflon.RTM. (registered trade name) and
having an opening diameter of 170 .mu.m and a nozzle opening
ejecting the liquid B was made of Teflon.RTM. (registered trade
name) and had an opening diameter of 250 .mu.m. The angle at which
the liquids A and B were brought into contact with each other was
35.degree..
[0195] The liquid A was a solution in which 7 parts by weight of
lipid-soluble dye Oil Green 502 (manufactured by Orient Chemical
Industries, Ltd.) and 7 parts by weight of polyoxyethylene cetyl
ether were dissolved in 50 parts by weight of tetrahydrofuran. As
the liquid B, ion-exchanged water was used.
[0196] The liquids A and B were supplied to the respective nozzles
using plunger pumps each used as a liquid supply unit. The liquid A
and the liquid B were supplied by the respective plunger pumps at
flow rates of 6 ml/min and 7 ml/min, respectively.
[0197] After the nozzles were placed in a manner similar to that of
Example 2, the liquids A and B were allowed to flow, so that a
spiral flow was formed. Since the coexistent polyoxyethylene cetyl
ether functioned as a dispersing agent, the lipid-soluble dye was
dispersed, and the average particle diameter was 50 nm.
Example 6
[0198] In this example, the case in which three types of liquids
were brought into contact with each other and were mixed together
to obtain a dispersion, as shown in FIG. 8, will be described.
[0199] In this case, three nozzles were all made of Teflon.RTM.
(registered trade name) tubes, a nozzle ejecting the liquid A had
an opening diameter of 250 .mu.m, a nozzle ejecting the liquid B
had an opening diameter of 250 .mu.m, and a nozzle ejecting the
liquid C had an opening diameter of 500 .mu.m.
[0200] The angle formed between the liquids was set to
50.degree..
[0201] 2,9-dimethyl quinacridone was used as a magenta pigment.
Into an eggplant-type flask having a volume of 300 ml, 10 parts by
weight of 2,9-dimethyl quinacridone was charged, and 100 parts by
weight of methanesulfonic acid was further added at room
temperature.
[0202] This eggplant-type flask was placed in an oil bath heated to
80.degree. C, and stirring was performed in an argon atmosphere for
10 minutes while heating was performed.
[0203] As a result, a quinacridone pigment solution having a
violet-blue color and containing 2,9-dimethyl quinacridone was
prepared.
[0204] Next, a solution in which 6.86 parts by weight of
polyoxyethylene cetyl ether functioning as a nonionic surfactant
was dissolved in 35 parts by weight of acetonitrile was added to 50
ml of the quinacridone pigment solution to prepare the liquid
A.
[0205] As the liquid B, a Pigment Yellow 151 solution was used
which was obtained by adding 50 parts by weight of a 6N aqueous
sodium hydroxide solution to 10 parts by weight of Pigment Yellow
151 and 8 parts by weight of polyoxyethylene cetyl ether.
[0206] As the liquid C, an aqueous polyoxyethylene lauryl ether
solution at a concentration of 0.1 percent by weight was used.
[0207] From the respective nozzles, the liquid A was ejected at a
flow rate of 5 ml/min by a syringe pump, and the liquid B was
ejected at a flow rate of 6 ml/min by a plunger pump. The liquid C
was ejected at a flow rate of 12.5 ml/min by a plunger pump to the
liquid-contact surface between the liquids A and B.
[0208] In this step, the nozzle ejecting the liquid C was shifted
so as to form a spiral flow after the three types of liquids were
brought into contact with each other. After the three types of
liquids were brought into contact with each other, a
re-precipitation reaction and dispersing occurred instantaneously,
so that an orange-colored dispersion was obtained. The dispersion
thus obtained was purified and condensed by ultrafiltration.
[0209] When the average particle diameter of the pigment fine
particles was measured using DLS-8000 (Otsuka Electronics Co.,
Ltd.), it was 95 nm, and a dispersion in which the particle
diameters were very uniform was obtained.
[0210] Accordingly, in the examples, after the nozzles are disposed
so that the liquids ejected from the respective nozzles are brought
into contact with each other and are then allowed to flow in an
integrated manner while forming a spiral flow, the liquids are
ejected from the nozzles. Accordingly, the examples show that flows
of the liquids are stabilized, and hence the liquids can be more
uniformly mixed together and can more uniformly react with each
other. As a result, a pigment dispersion in which particles have a
smaller diameter and a narrower particle distribution can be
obtained.
[0211] In addition, the examples show that the liquid mixing device
described therein is a suitable device for carrying out a method
according to aspects of the present invention.
[0212] While the present invention has been described with
reference to exemplary embodiments, it is to be understood that the
invention is not limited to the disclosed exemplary embodiments.
The scope of the following claims is to be accorded the broadest
interpretation so as to encompass all modifications and equivalent
structures and functions.
[0213] This application claims the benefit of Japanese Application
No. 2008-165078 filed Jun. 24, 2008 and No. 2008-278426 filed Oct.
29, 2008, which are hereby incorporated by reference herein in
their entirety.
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